What is a CAJ file?
A .CAJ file is most often a Chinese Academic Journal File. It is the standard digital document format created by the China National Knowledge Infrastructure (CNKI). Academic researchers use .CAJ files to store, share, and read research papers, dissertations, and scientific articles published in China. Less frequently, a .CAJ file might be a sheet metal cutting job file used by Lantek CAD/CAM software.
How to open CAJ files?
Opening a .CAJ file usually requires dedicated viewing software. Some .CAJ files contain a modified .PDF or .KDH internal structure, but standard PDF readers cannot open them directly because of proprietary wrappers. Because a .CAJ file can belong to completely different software families, you should verify its true format first.
Software and tools
The official software to open academic .CAJ documents is CAJViewer. It is developed by Tsinghua Tongfang and is available for Windows, Mac, and mobile platforms. For the manufacturing variation, you need Lantek Expert. Advanced users can also use open-source command-line tools like caj2pdf to strip the proprietary wrapper and convert compatible .CAJ files into standard PDF format.
Summary
viewer.online/caj can analyze .CAJ files to identify the exact format and creator software, inspect the file structure, extract readable text, and check whether an online preview is available. This makes viewer.online/caj highly useful for identifying, inspecting, and understanding .CAJ files without installing software or dealing with compatibility problems.